1. Field of the Invention
The present invention relates to a power supply apparatus having a battery, and more particularly relates to a power supply apparatus that can detect a deterioration of a battery.
2. Description of the Related Art
A conventional typical power supply apparatus has an emergency battery so that a power supply to a load is not interrupted even in a case of a stop of an input power from a commercially alternating power supply or the like. As a power supply apparatus having a battery, Japanese Utility Model Publication (unexamined) No. U-6-37991 discloses an emergency report apparatus for periodically discharging a battery, and then judging whether or not the battery is deteriorated, and further reporting the deterioration.
This emergency report apparatus is provided with a charging battery, a first diode, a second diode, a first resistor, a second resistor, a first switch, a second switch, a third switch and a voltage detecting circuit. Also, a direct current power supply and a load circuit and CPU are connected to peripheral parts of the emergency report apparatus. The charging operation to the charging battery is carried out by establishing a connection between a positive side of the charging battery and a terminal side of the first resistor through the first switch and then creating the circuit in the order of the direct current power supply, the first diode, the first resistor and the charging battery. The current flowing through the charging battery is disconnected by opening the first switch and thereby disconnecting the connection between the positive side of the charging battery and the terminal side of the first resistor. The charging battery is discharged through the second resistor from the charging battery by establishing a connection between the second resistor and the positive side of the charging battery through the second switch. After that, in the emergency report apparatus, the positive side of the charging battery and a cathode side of the second diode are connected to each other by the second switch. An anode side of the second diode, a cathode side of the first diode and the circuit serving as the load are disconnected by the third switch. Accordingly, the load circuit connected through the charging battery, the second switch, the second diode and the third switch is at an open state. Then, this emergency report apparatus sends a signal indicative of a drop in a capacity of the charging battery to the CPU, if an open voltage detected by the voltage detecting circuit connected between the second switch and the positive side of the charging battery becomes equal to or less than a set value.
As another conventional example, Japanese Laid Open Patent Application (JP-A-Heisei, 2-55536) discloses a battery life judging circuit for an uninterruptible power supply apparatus. This uninterruptible power supply apparatus is provided with: a power converter for converting an electric power from a direct current power supply and supplying the electric power to a load; and a battery for supplying an electric power to the power converter instead of the direct current power supply at a time of a service interruption of the direct current power supply. Moreover, the battery life judging circuit for the uninterruptible power supply apparatus is provided with: a device for artificially interrupting the direct current power supply; a device for temporally integrating the currents discharged by the battery in the period until a voltage is dropped by a predetermined value from a battery voltage at a time of this artificial service interruption occurrence; and a device for judging whether or not this temporally integrated value of the currents is equal to or less than a predetermined value.
Japanese Laid Open Patent Application (JP-A-Heisei, 3-18781) discloses a battery check method. This conventional technique is provided with: a rectifying circuit for rectifying and outputting a current from an alternating power supply; and a voltage converter for converting and outputting a voltage of a battery at a time of a service interruption of the alternating power supply. These two output are combined and supplied to the load. This battery check method contains a control circuit for instructing the voltage converter to output an output voltage higher than an output voltage of the rectifying circuit, on the basis of an outer signal in a non-interruption period of the alternating power supply, and detects the deterioration of the battery and the charging/discharging condition thereof from a change in a terminal voltage of the battery when an electric power is supplied to a load from the battery.
Japanese Laid Open Patent Application (JP-A-Heisei, 6-105483) discloses an alternating uninterruptible power supply apparatus. In this conventional technique, an inverter which uses a battery as a power supply successively supplies an electric power to a load apparatus at a time of a voltage drop in a normal power supply or a service interruption. This alternating uninterruptible power supply apparatus defines a start order as an order of a charger, the inverter and an AC/DC converter, and then carrying out a discharge of a certain electric power from the battery. So, it has the functions of supposing an inner resistor of the battery on the basis of a voltage prior to a discharging operation from the battery and a voltage after a certain temporal elapse from the start of the discharging operation or a voltage drop value, and easily detecting and judging a life end of the battery, and further reporting this judged result to an external portion.
Also, Japanese Laid Open Patent Application (JP-A Heisei, 9-237640) discloses a battery deterioration state tester for an alternating uninterruptible power supply apparatus. This battery deterioration state tester for the alternating uninterruptible power supply apparatus judges the deterioration degree in the battery of the alternating uninterruptible power supply apparatus, which uses a battery connected through a breaker as a power supply in a case of a service interruption of an alternating power supply, and supplies an alternating electric power from an inverter circuit to a load. In this tester, a charge is discharged to the load through the inverter circuit from the battery, and the judgment is done on the basis of the discharged condition. Also, this battery deterioration state tester has a discharge test stopper, which after the start of the discharging operation, a voltage change rate of an input voltage to the inverter circuit is measured to accordingly stop the discharge test if the voltage change rate is greater than a predetermined standard value.
By the way, according to the technique disclosed in Japanese Laid Open Patent Application (JP-A-Heisei, 6-37991) the conventional power supply apparatus carries out the discharging operation after the charging battery is perfectly separated from the circuit as the load. For this reason, in this conventional power supply apparatus, if the commercial alternating power supply or the like is interrupted, the supply of the electric power is stopped from the direct current power supply after the AC/DC conversion. This results in the drop in the output to the load side.
The present invention is proposed in view of the above-mentioned circumstances.
It is therefore an object of the present invention to provide a power supply apparatus that can detect a deterioration of a battery without any drop in an output voltage to a load side, at a time of a service interruption of an alternating power supply.
Another object of the present invention is to provide a power supply apparatus that can detect a deterioration of a battery without any drop in an output voltage to a load side, even if the battery deterioration causes an output voltage from the battery to be instantly dropped, at a time of a detection of the battery deterioration.
The devices for solving the above-mentioned problems are represented as follows. Numbers, symbols and the like are affixed to the technical items corresponding to the claims in the representation. The numbers, the symbols and the like coincide with reference numbers, reference symbols and the like which are affixed to the technical items constituting at least one implementation or a plurality of embodiments among a plurality of implementations or a plurality of embodiments of the present invention, especially, the technical items represented in the drawings corresponding to the implementations or the embodiments. The numbers, the symbols and the like clarify the correspondence and relation between the technical items noted in the claims and the technical items of the implementations or the embodiments. However, the above-mentioned correspondence and relation are not intended to imply that the technical items noted in the claims are limited to the technical items in the implementations or the embodiments.
A power supply apparatus according to the present invention is the power supply apparatus connected to a load circuit 2, and it is provided with a battery charge controller 52 that is connected to a battery 28 and charges the battery 28 at a first voltage, an electric power is supplied to the load circuit 2 from the battery 28 or the battery charge controller 52. Moreover, it includes a diagnosing circuit 18 for diagnosing the deterioration of the battery 28, in accordance with a battery voltage. It should be noted, the battery 28 is excluded from the battery charge controller 52.
Moreover, a power supply apparatus according to the present invention is the power supply apparatus connected to a load circuit 2, and it is provided with: a battery charge controller 52 that is connected to a battery 28 and charges the battery 28 at a first voltage; and a voltage controller 51 that is connected to the load circuit 2 and generates a second voltage and controls the second voltage so as to make a voltage supplied to the load circuit 2 constant. An electric power is supplied to the load circuit 2 from at least one of the battery 28, the battery charge controller 52 (however, except the battery) and the voltage controller 51.
Moreover a power supply apparatus according to the present invention is the power supply apparatus connected to a load circuit 2, and it is provided with: a battery charge controller 52 that is connected to a battery 28 and charges the battery 28 at a first voltage; and a voltage controller 51 that is connected to the load circuit 2 and generates a second voltage and controls the second voltage so as to make a voltage supplied to the load circuit 2 constant. An electric power is supplied to the load circuit 2 from at least one of the battery 28, the battery charge controller 52 and the voltage controller 51. Moreover, it includes a diagnosing circuit 18 for diagnosing the deterioration of the battery 28, in accordance with a battery voltage.
Moreover a power supply apparatus according to the present invention further includes an inserting unit 43 for inserting a dummy load 42 into the load circuit 2 in series so as to make a current supplied to the load circuit 2 constant.
Moreover a power supply apparatus according to the present invention further includes a current measuring circuit 41 for measuring a value of a current supplied from the battery 28 or the battery charge controller 52, and controlling the inserting unit 43 so as to insert the dummy load 42 into the load circuit 2 in series, on the basis of the measured value and a set current value.
The battery charge controller 52 receives an alternating voltage and generates the first voltage. The diagnosing circuit 18, when an input of the alternating voltage is stopped during a diagnosis of a deterioration of the battery 28, stops the diagnosis of the deterioration of the battery 28. And, an electric power is supplied to the load circuit 2 from the battery 28 or the battery charge controller 52.
The diagnosing circuit 18 outputs a charging control signal to the battery charge controller 52, and the battery charge controller 52 charges the battery voltage in response to the charging control signal.
Moreover the diagnosing circuit 18 compares the battery voltage with a set voltage, and diagnoses the deterioration of the battery 28 in accordance with the compared result.
Moreover a power supply apparatus according to the present invention further includes an electrical reception monitor 14 for monitoring an electrical reception condition of an alternating voltage and outputting an electrical reception signal to the diagnosing circuit 18. The battery charge controller 52 receives the alternating voltage and generates the first voltage. And, the diagnosing circuit 18 stops or resumes the diagnosis of the deterioration of the battery 28, in response to the electrical reception signal.
Moreover a power supply apparatus according to the present invention further includes a period setting circuit 20 for setting a set period. The diagnosing circuit 18, if the electrical reception of the alternating voltage is stopped in the set period set by the period setting circuit 20, stops the diagnosis of the deterioration of the battery 28, and if the electrical reception of the alternating voltage is recovered, resumes the diagnosis of the deterioration of the battery 28.
A method of diagnosing a deterioration of a battery, in a power supply apparatus of the present invention is a power supply apparatus connected to a load circuit 2, comprising the steps of: (a) charging a battery 28 at a first voltage; (b) setting a set voltage; (c) comparing a battery voltage with the set voltage; (d) diagnosing the deterioration of the battery 28 in accordance with the result compared at the step (c); and (e) supplying the battery voltage or the first voltage to the load circuit 2.
Moreover a method of diagnosing a deterioration of a battery, in a power supply apparatus of the present invention is a power supply apparatus connected to a load circuit 2, comprising the steps of: (a) charging a battery 28 at a first voltage; (b) setting a set voltage; (c) comparing a battery voltage with the set voltage; (d) diagnosing the deterioration of the battery 28 in accordance with the result compared at the step (c); (f) generating a second voltage, and controlling the second voltage so as to make a voltage supplied to the load circuit 2 constant; and (g) supplying at least one voltage of the battery voltage, the first voltage and the second voltage to the load circuit 2.
Moreover a method of diagnosing a deterioration of a battery, in a power supply apparatus of the present invention further includes the step of: (h) inserting a dummy load 42 into the load circuit 2 in series so as to make a current supplied to the load circuit 2 constant.
Moreover a method of diagnosing a deterioration of a battery, in a power supply apparatus of the present invention further includes the step of: (i) setting a set current; (j) measuring a value of a current supplied from the battery 28 or a current corresponding to the second voltage; and (k) inserting the dummy load 42 into the load circuit 2 in series, on the basis of the set current and the value measured at the step (j).
Moreover a method of diagnosing a deterioration of a battery, in a power supply apparatus of the present invention further includes the steps of: (1) setting a set period; (m) executing the step (c) and the step (d) at a time of an elapse of the set period; (n) receiving an alternating voltage; (o) monitoring an electrical reception of the alternating voltage, in accordance with the set period; (p) stopping the step (c) and the step (d) when the electrical reception of the alternating voltage is stopped; and (q) resuming the step (c) and the step (d) when the electrical reception of the alternating voltage is recovered.
Moreover a method of diagnosing a deterioration of a battery, in a power supply apparatus of the present invention further includes the steps of: (r) stopping the step (c) and the (d) when the battery 28 is diagnosed as a deterioration at the step (d); and (s) resuming the step (c) and the step (d) when the battery diagnosed as the deterioration is recovered.
From the above-mentioned explanations, the power supply apparatus according to the present invention, when diagnosing the battery deterioration, uses the actually connected load 2 as the load to be used to forcedly discharge the battery 28. Thus, even if the AC power supply is accidentally interrupted during the diagnosis of the battery deterioration, the DC output is supplied in its original state from the battery 28 to the load 2. Hence, the battery deterioration can be diagnosed without any drop in the output to the load side.
Also, the power supply apparatus according to the present invention is characterized in that at the time of the battery deterioration diagnosis, even if the battery deterioration causes the DC output from the battery 28 to be instantly dropped, the output to the connected load side is not dropped. In the battery deterioration diagnosis of the power supply apparatus 1, 101 according to the present invention, the minimum DC voltage is reserved in the AC/DC converter 151. So, when the battery deterioration diagnosing unit 53 diagnoses the battery deterioration, even if the battery deterioration causes the DC output from the battery 28 to be instantly dropped, the minimum DC voltage can be outputted to the load 2 from the AC/DC converter 51 without any influence on the load 2 side.